Method and System for Disabling an Electronic Device

ABSTRACT

A portable electronic device. The portable electronic device is dependently operable on being remotely coupled to at least one RFID tag, the RFID tag being disposed on one of a piece of jewelry or a portion of clothing worn on a person. Upon removal of the jewelry or clothing the RFID tag is rendered inoperable and the electronic device is partially or completely disabled.

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Application61/452,158, entitled System and Method for Disabling an ElectronicDevice, filed Mar. 14, 2011. This application also claims priority toU.S. Provisional Application 61/438,739, entitled System and Method forDisabling an Electronic Device, filed May 8, 2011.

TECHNICAL FIELD

The invention relates to portable electronic devices, including cellulartelephones, Smartphone, iPads, tablet computing devices, netbooks,laptop computers, and the like. The invention relates more particularlyto methods and systems to mitigate the risk of information loss orunauthorized use due to device loss or theft.

BACKGROUND OF THE INVENTION

Portable and handheld computing devices, including cellular telephones,Smartphone, iPads, tablet computing devices, netbooks, laptop computers,and the like are becoming more prevalent in modern society. Thesedevices increasingly contain information about and access to an owner'spersonal life and personally identifiable information. For example,these devices can have stored in memory the user's credit cardinformation. These devices are also increasingly performing morefunctions, such as replacing car keys for starting an automobile, orholding confidential business information.

Clearly, the loss of a modern handheld computing device can cause greatinjury to the owner. A lost or stolen device may permit the finder orthief to access the legitimate owner's personally identifiableinformation and other information such as banking or medical records.The unauthorized user can misappropriate personal property such as acar, misappropriate real property such as a house, and otherwise stealthe legitimate user's identity.

Current safeguards, such as password protection are not sufficient. If,for example, a handheld computing device is stolen after the user entersthe password, the device can be used by the thief.

There is a continuing unaddressed need for product, system, or methodfor ensuring a higher degree of device protection against loss or theft.

SUMMARY OF THE INVENTION

A portable electronic device is disclosed. The portable electronicdevice is dependently operable on being remotely coupled to at least oneRFID tag, the RFID tag being disposed on one of a piece of jewelry or aportion of clothing worn on a person. Upon removal of the jewelry orclothing the RFID tag is rendered inoperable and the electronic deviceis partially or completely disabled.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below withreference to the following accompanying drawings.

FIG. 1 is a block diagram of a system of the present invention,including a tag and reader in which the invention could be incorporated.

FIG. 2 is a flowchart illustrating steps performed in one embodiment ofthe present invention.

FIG. 3 is a block diagram of an embodiment of an RFID communicationsystem, including a tag and reader, embodying various aspects of theinvention.

FIG. 4 is a flowchart illustrating steps performed by the tag and readerof FIG. 3.

FIG. 5 is a block diagram of an illustrative RF addressable sensornetwork according to an embodiment of the present invention.

FIG. 6 is a block diagram of an illustrative RF addressable sensoraccording to embodiments of the present invention.

FIG. 6A is a block diagram of an illustrative RF addressable sensoraccording to embodiments of the present invention.

FIG. 7 is a block diagram of a wireless sensor reader according toembodiments of the present invention.

FIGS. 8A, 8B, and 8C are block diagrams of wireless sensor readerconfigurations according to embodiments of the present invention.

FIG. 9 is a flowchart illustrating an operational sequence of RFaddressable sensor read communications from the perspective of thewireless sensor reader according to an embodiment of the presentinvention.

FIG. 11A is a flowchart illustrating a method of RF addressable sensorread communications from the perspective of a basic single RFaddressable sensor reader according to an embodiment of the presentinvention.

FIG. 11B is flowchart illustrating a method of RF addressable sensorread communications from the perspective of an RF addressable sensorhaving local processing capabilities according to an embodiment of thepresent invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The following US patents and applications are incorporated herein byreference for their enabling teaching of methods, systems, and devicesrelated to remote wireless communication: U.S. patent application Ser.No. 10/263,826 entitled “Radio Frequency Identification DeviceCommunications Systems, Wireless Communication Devices, WirelessCommunication Systems, Backscatter Communication Methods, A RadioFrequency Identification Device and A Radio Frequency IdentificationDevice Communication Method” by inventors Mike A. Hughes and Richard M.Pratt; U.S. patent application Ser. No. 10/263, 809, entitled “Method ofSimultaneously Reading Multiple Radio Frequency Tags, RF Tag, and RFReader”, by inventors Emre Ertin, Richard M. Pratt, Mike A. Hughes,Kevin L. Priddy, and Wayne M. Lechelt; U.S. patent application Ser. No.10/263, 873, entitled “RFID System and Method Including Tag IDCompression”, by inventors Mike A. Hughes and Richard M. Pratt; U.S.patent application Ser. No. 10/264,078, entitled “System and Method toIdentify Multiple RFID Tags”, by inventors Mike A. Hughes and Richard M.Pratt; U.S. Patent application Ser. No. 10/263,940, entitled “WirelessCommunication Devices, Radio Frequency Identification Devices,Backscatter Communication Device Wake-Up Methods, Communication DeviceWake-Up Methods and A Radio Frequency Identification Device Wake-UpMethod”, by inventors Richard Pratt and Mike Hughes; U.S. patentapplication Ser. No. 10/263,997, entitled “Wireless CommunicationSystems, Radio Frequency Identification Devices, Methods of Enhancing aCommunications Range of a Radio Frequency Identification Device, andWireless Communication Methods”, by inventors Richard Pratt and StevenB. Thompson; U.S. patent application Ser. No. 10/263,670, entitled“Wireless Communications Devices, Methods of Processing a WirelessCommunication Signal, Wireless Communication Synchronization Methods anda Radio Frequency Identification Device Communication Method”, byinventors Richard M. Pratt and Steven B. Thompson; U.S. patentapplication Ser. No. 10/263,656, entitled “Wireless CommunicationsSystems, Radio Frequency Identification Devices, Wireless CommunicationsMethods, and Radio Frequency Identification Device CommunicationsMethods”, by inventors Richard Pratt and Steven B. Thompson; U.S. patentapplication Ser. No. 09/589,001, filed Jun. 6, 2000, entitled “RemoteCommunication System and Method”, by inventors R. W. Gilbert, G. A.Anderson, K. D. Steele, and C. L. Carrender; U.S. patent applicationSer. No. 09/802,408, filed Mar. 9, 2001, entitled “Multi-Level RFIdentification System”, now U.S. Pat. No. 6,765,476; by inventors R. W.Gilbert, G. A. Anderson, and K. D. Steele; U.S. patent application Ser.No. 09/833,465, filed Apr. 11, 2001, entitled “System and Method forControlling Remote Device”, by inventors C. L. Carrender, R. W. Gilbert,J. W. Scott, and D. Clark; U.S. patent application Ser. No. 09/588,997,filed Jun. 6, 2000, entitled “Phase Modulation in RF Tag”, by inventorsR. W. Gilbert and C. L. Carrender; U.S. patent application Ser. No.09/589,000, filed Jun. 6, 2000, entitled “Multi-Frequency CommunicationSystem and Method”, by inventors R. W. Gilbert and C. L. Carrender, nowU.S. Pat. No. 6,745,008; U.S. patent application Ser. No. 09/588,998,filed Jun. 6, 2000, entitled “Distance/Ranging by Determination of RFPhase Delta”, by inventor C. L. Carrender; U.S. patent application Ser.No. 09/797,539, filed Feb. 28, 2001, entitled “Antenna MatchingCircuit”, by inventor C. L. Carrender, now U.S. Pat. No. 6,738,025; U.S.patent application Ser. No. 09/833,391, filed Apr. 11, 2001, entitled“Frequency Hopping RFID Reader”, by inventor C. L. Carrender; U.S.patent application Ser. No. 12/287,565, filed Oct. 9, 2008, entitled“Electronic Device with Radio Frequency Identification (RFID)Technology, inventors Yu Zhao and Hui Yang.

The invention addresses the problem of loss by, or theft from, arightful user of a portable electronic device. In general, as describedin detail herein, the invention involves the portable electronic devicebeing in dependent operable communication with a portable remote coupleddevice. In an embodiment the portable electronic device is selected fromthe group consisting of a telephone, a cellular telephone, a Smartphone,a tablet device, such as an iPad, and the like. In an embodiment,communication is via radio frequency and the remote coupled device is aRadio Frequency Identification (RFID) device, commonly called an RF tag,and at times referred to herein as an RF addressable sensor.

In an embodiment, the portable electronic device is a Smartphone, andwireless communication is via radio frequency and one or more remotecoupled devices include one or more RFID devices.

As used herein the term Smartphone is used in its normal, acceptedmeaning, including device that is a cellular telephone with built-inapplications and Internet access. Smartphones can provide digital voiceservice as well as text messaging, e-mail, Web browsing, still and videocameras, MP3 player, video viewing and often video calling. CurrentlySmartphones operate on known operating systems, such as Symbian,Android, Blackberry, Apple iOS, and Windows, each operating system ofwhich can be adapted by known means by persons of ordinary skill asnecessary for the invention described herein.

While not intending to be limited to current technology and currentconvention, in general, for RFID technology, the present inventionfollows the following convention with respect to common radio frequencybands: Low Frequency (LF), <135 kHz, including 120 to 150 kHz, or 125 to134 kHz; High Frequency (HF), 13.56 MHz, including 13.533 to 13.567 MHz,(sometimes referred to as “Medium Frequency” and also is used for theISM band worldwide); Ultra High Frequency (UHF), 433 MHz and 860 to 956MHz; Microwave Frequency, 2.45 to 5.8 GHz. Further information withrespect to frequency ranges and allowed fieldstrength/transmission powercan be obtained at the disclosure of http://rfid-handbook.com/, which ishereby incorporated by reference herein.

By “dependent operable communication” is meant that the operation of theportable electronic device is at least partially dependent upon being incommunication with the remote device to which it is coupled, such as byradio frequency communication. Once the coupling is broken, the portableelectronic device is no longer in communication with the coupled device,and is, therefore, no longer operable or at least partially disabled.

By “remote” is meant wirelessly separated. For example, a wirelesscomputer mouse and a computer having a sensor to sense the wirelessmouse, are each remote from the other and coupled for operablecommunication.

In one embodiment, the portable electronic device can be in completedependent operable communication, in which case upon breaking of thecoupling with the remote device, the portable electronic device isimmediately and completely disabled such that it can perform nofunctions. A completely disabled electronic device is one which is in astate equivalent to “off”.

In one embodiment, the portable electronic device can be in limiteddependent operable communication, in which case upon breaking of thecoupling with the remote device, the portable electronic device isdisabled to a limited extent, such that it can perform some functionsbut not others. A partially disabled electronic device is one which isin a state equivalent to “on” but for which some functionality isblocked. For example, in an embodiment, the portable electronic devicecan be in limited dependent operable communication, such that uponbreaking of the coupling with the remote device, the portable electronicdevice is disabled except to receive a passcode, password, or the like.That is, a correctly entered password can override the disabling due tobeing out of range of the remote coupled device.

In an embodiment, the portable electronic device can be in limiteddependent operable communication, such that upon breaking of thecoupling with the remote device, the portable electronic device isdisabled except to operate with predetermined approved functions, suchas a telephone; that is, the device can access no data from memory andno access can be made to stored data such as email data. In this mode,the device can be used as a telephone, but no sensitive data stored onthe device can be accessed, and no functions such as electronic walletfunctions can be utilized.

As shown in FIG. 1, a basic system 10 of the present invention includesa portable electronic device 11 having as a part thereof an interrogator18. The system 10 also includes at least one transponder, or RFaddressable sensor, which can be an RF tag 16. The interrogator 18includes a transceiver which can include a decoder 14 and an antenna 12.The tag 16 includes an antenna 24. In operation, the antenna 12 emitsand receives electromagnetic radio signals generated by the transceiver14 to activate the tag 16 and receive signals from the tag. When the tag16 is activated, data can be read from or written to the tag. The RF tagdata can be configured or programmed so that the interrogator 18 canrecognize an RF tag intended to be recognized, and, therefore,considered “coupled” to the interrogator.

The interrogator 18 can emit radio signals 20 in a range from one inchto one hundred feet or more, depending upon its power output and theradio frequency used. When a coupled RF tag 16 is within range of theelectromagnetic radio waves 20, the tag detects the signal 20 and isactivated. Data encoded in the coupled RF tag 16 can then be transmittedby a modulated data signal 22 through an antenna 24 to the interrogator18 for subsequent processing.

When interrogator 18 receives data signal 22, portable electronic device11 can operate normally for all functions. However, if portableelectronic device 11 and coupled RF tag 16 become separated by adistance beyond which either radio waves 22 or data signal 22 can bedetected, then portable electronic device 11 can become eithercompletely or partially disabled.

In one mode of operations, therefore, a user of a portable electronicdevice of the invention can have on his or her body, in his or herwallet or purse, in his or her clothing, or in his or her automobile acoupled RF tag 16. As long as the user is in possession of the portableelectronic device 11, and is, therefore in range of the coupled RF tag16, the portable electronic device 11 works normally. But if theportable electronic device is lost, stolen, or otherwise not in closeproximity to the user, the device, being out of range of the coupled RFtag, becomes either completely or partially disabled.

An embodiment of a method of the present invention utilizing an RF tagas a remote coupled device is described with respect to the flowchart ofFIG. 2. At Step A, SA, the requestor, which can be a component of theportable electronic device 11 e.g., a built-in interrogator, emits asignal. At Step B, SB, the interrogator's transceiver either receives asignal from a remote coupled RF tag or it doesn't. Again, by “coupled RFtag” is meant an RF tag intended to be a part of the system, such thatupon detection, which can be by receipt of a predetermined coded signal,the portable electronic device becomes or remains operable.

If at SB the interrogator does not receive a signal from the coupled RFtag, or at least one of multiple coupled RF tags, the system can executeat Step C, SC, an optional step of querying for a password or passcode.The purpose of the optional passcode is in anticipation of events inwhich the rightful user of the portable electronic device may not be inoperable proximity to the coupled RF tag, or may lend the portableelectronic device to another who does not have the coupled RF tag, orother events in which the rightful owner desires to use the portableelectronic device in the absence of the coupled RF tag.

If at optional SC a proper passcode is entered, or, if at SB a remotecoupled RF tag was detected, then at Step D, SD, executable instructionsin the device memory of the portable electronic device can be utilizedto enable the portable electronic device to operate fully for itsintended purpose. Instructions from device memory or executableinstructions can be identical or similar to such instructions and memoryutilized on current devices that are enabled upon entering a passcode.

However, if the coupled RF tag is not detected and, optionally, if apasscode is not entered, at Step E, SE, executable instructions in thedevice memory of the portable electronic device either partially orfully disable the portable electronic device, rendering it eitherpartially or fully inoperable.

In one embodiment, partial disablement of a portable electronic deviceincludes disabling all internet access, all document storage, all bankaccount information and banking capability, or all memory containingpersonally identifiable information, but enabling or continuing toenable telephone service. In this embodiment, a rightful user can stilluse the telephone function, which, in other embodiments of the inventioncan be utilized to enable further functionality.

In an embodiment disablement is complete; that is, the device iscompletely “off” with no powered operations. In an embodimentdisablement is powered partial, in that the device can be “on” but nofunctions can be utilized until a remote coupled device is detectedand/or a passcode is entered. In an embodiment disablement isfunction-specific partial, in that the device can be “on” but certainpredetermined functions, such as the telephone function, can be utilizeduntil a remote coupled device is detected and/or a passcode is entered,at which time full functionality can be restored.

Referring back to FIG. 2, once the remote coupled device is detected andthe portable electronic device is operable, the cycle can be repeated asStep F, SF, at predetermined intervals. The predetermined intervals canbe from a range of once every millisecond to once every half hour, therange including every millisecond interval in between. Thus, one minute,two minutes, ten minutes, and every other multiple of millisecondsbetween one and half an hour, are literally disclosed herein.

The method described in FIG. 2 can run as a loop constantly, providingfor constant, uninterrupted operation of a portable electronic deviceunless and until a remote coupled device is not detected, at which timeoperation is partially or fully disabled, as predetermined by the user.As such, in an embodiment, the invention can be described as a portableelectronic device in dependent operable communication with a remotecoupled device. That is, operation of the electronic device is dependentupon its being in range of a remote coupled device, e.g., an RF tag.

In an embodiment the remote coupled device can be an RF tag associatedwith the rightful user's credentials for workplace security. Forexample, if the user has an access badge or other object containing anRF tag, the RF tag can be used not only for the user's othersecurity-related activities, such as building entry, but can also serveas the remote coupled device for the user's portable electronic device.In this manner, an employee with a company-issued portable electronicdevice need not carry on his or her person RF tags; the RF tag forcompany security can be designed or programmed to also be the remotecoupled device for portable electronic device security.

In an embodiment, the electronic device is not portable. For example,the methods, systems, and apparatus of the present invention can beapplied with beneficial results to the use of a desktop computer, forexample. In the context of a desktop the threat may not be loss or theftof the device, but the benefit can be convenience and protection againstunauthorized use. If the desktop computing device detects the remotecoupled device, the user at the desktop need not enter any passwords foruse of the desktop computer.

Although other remote coupled devices, such as powered radiotransceivers, are contemplated for use as the remote coupled device, anadvantage of RFID systems and RF tags is the small size of thenon-contact, non-line-of-sight capability of the technology. RF tags canbe thin enough to keep on a card in one's wallet or attached toclothing, and small enough to be embedded in dentures are swallowed in acapsule, but they can be read through a variety of substances such assnow, fog, ice, paint, dirt, clothing and other visually andenvironmentally challenging conditions where other remote devices, suchas bar codes or other optically-read technologies, would be useless. RFtags can also be read at remarkable speeds, in some cases responding inless than one hundred milliseconds.

There are three main categories of RFID tag systems that can be used asthe remote coupled devices of the invention. These are systems thatemploy beam-powered passive tags, battery-powered semi-passive tags, andactive tags. Each operates in fundamentally different ways. Theinvention described herein can be embodied in any of these types ofsystems.

The beam-powered RFID tag is often referred to as a passive devicebecause it derives the energy needed for its operation from the radiofrequency energy beamed at it. The tag rectifies the field and changesthe reflective characteristics of the tag itself, creating a change inreflectivity that is seen at the interrogator. A battery-poweredsemi-passive RFID tag operates in a similar fashion, modulating its RFcross-section in order to change its reflectivity that is seen at theinterrogator to develop a communication link. Here, the battery is theonly source of the tag's operational power. Finally, in the active RFIDtag, both the tag and reader have transceivers to communicate and arepowered by a battery.

The range of communication for RF tags varies according to thetransmission power of the interrogator 18 and the RF tag 16.Battery-powered tags operating at 2,450 MHz can be limited to less thanten meters in range. However, devices with sufficient power can reach inexcess of 100 meters in range, depending on the frequency andenvironmental characteristics. RF tags of the present invention can bechosen as desired; for general use a range of ten meters can besufficient, as most people never intentionally go more than ten metersfrom their portable electronic devices, especially when the devicescontain valuable information or functionality, such as the ability tostart one's car or make point-of-sale credit card purchase. However, forsome uses, an RF tag in one's car, for example, with a range of 100meters, may suffice for every day uninterrupted operation.

RF tag systems can utilize continuous wave backscatter to communicatedata from the RF tag 16 to the interrogator 18. More specifically, theinterrogator 18 can transmit a continuous-wave radio signal to the tag16, which modulates the signal 20 using modulated backscattering whereinthe electrical characteristics of the antenna 24 are altered by amodulating signal from the tag that reflects a modulated signal 22 backto the interrogator 18. The modulated signal 22 can be encoded withinformation from the tag 16. The interrogator 18 can then demodulate themodulated signal 22 and decodes the information. In the presentinvention, the decoded information can identify a coupled remote RF tag,thereby permitting operation of the portable electronic device.

Conventional continuous wave backscatter RF tag systems utilizingpassive (no battery) RF tags require adequate power from the signal 20to power the internal circuitry in the tag 16 used to modulate thesignal back to the interrogator 18. While this is successful for tagsthat are located in close proximity to an interrogator, for example lessthan three meters, this may be insufficient range for some applications,for example greater than 100 meters. In the present invention, it iscontemplated that most users will likely have the remote coupled RF tagon their person, such as in a pocket, a purse, a wallet, or hidden inclothing, so that passive RF tags can be utilized for the presentinvention.

The system of the invention can utilize more than one RF tag 16 for eachportable electronic device 11. For example, a user can have a coupled RFtag in his or her car and on his or her person. Likewise, the user mayhave a coupled RF tag in one or more of his or her clothing, his or herhouse or office, his or her purse or brief case, office, and the like.When more than one RF tag 16 is utilized, the system can operate in amode that requires one or more of the RF tags to be in range. Likewise,a building may contain multiple RF tags placed throughout so thatoccupants of the building can utilize the system without having toconcern themselves with having RF tags on their person.

When more than one RF tag 16 is utilized, the system can operate in amode in which the portable electronic device 11 is disabled, eithercompletely or partially, only when all of the RF tags are out of range.

Therefore, in an embodiment, the invention can be described as aportable electronic device in dependent operable communication with atleast one of a plurality of remote coupled devices.

When more than one RF tag 16 is utilized, the system can operate in amode in which the portable electronic device 11 is disabled, eithercompletely or partially, if any one of the RF tags is out of range.

Therefore, in an embodiment, the invention can be described as aportable electronic device in dependent operable communication with allof a plurality of remote coupled devices. Coupling can be by radiofrequency signal transmission.

In an embodiment, more than one portable electronic device can becoupled to one or more remote coupled devices. In this manner, arightful user of two portable electronic devices, such as a telephoneand a tablet computer, can have both portable electronic devices coupledto a single RF tag.

Therefore, in an embodiment, the invention can be described as at leastone portable electronic device, each portable electronic device independent operable communication with at least one remote coupleddevice.

Having more than one RF tag 16 remotely coupled to a portable electronicdevice 11 has many advantages. For example, if the system is set up topermit operation of portable electronic device 11 when in range of atleast one, but not all, RF tags 16, then the user need not worry if heor she has an RF tag on her person at all times; she need only have anRF tag in her car, her home, office, and the like. If the system is setup to permit operation of the portable electronic device 11 only if allRF tags 16 are in range, then if a thief steals the user's portableelectronic device 11 and a coupled RF tag 16 from the user's person,then the portable electronic device can still be disabled when theportable electronic device 11 goes out of range of any one of another ofthe remotely coupled RF tags 16, such as a coupled RF tag 16 in theuser's car.

In an embodiment, the operation of multiple RF tags can be set remotely,such as by telephone or internet web address, by a rightful owner of aportable electronic device. In this manner, the rightful owner can setor change the parameters of use, including the operation of RF tags. Forexample, if the system is set to operate in a mode in which the portableelectronic device 11 is enabled, either completely or partially, if anyone of the RF tags 16 is in range, and the device is stolen, therightful owner, via telephone or internet web access, can change theoperation so that the device is disabled if it is out of range of anyone of the RF tags. Likewise, the rightful owner can simply change themode of operation to completely disable the device, regardless of theproximity of any remotely coupled devices. Telephone or web accessintervention can be contingent upon the rightful owner producing anaccess code, passcode, password, or the like.

The method, systems, and apparatus of the invention can utilizeprocedures to authenticate and secure communications between theportable electronic device and any coupled RF tag(s). One method ofauthentication is described with respect to FIG. 3.

As shown in FIG. 3, an embodiment of the present invention havingenhanced authentication utilizes an RF communication system 30 between aportable electronic device 11 and a remote coupled device, e.g., aprocessor-containing RF tag 44 that employs backscatter signals. The RFcommunication system 30 includes a portable electronic device 11containing a reader or interrogator 32 that includes an antenna 34through which the reader can transmit an interrogation signal 36 to anRF tag 44. The RF tag 44 modulates the continuous wave interrogationsignal 36 to produce a backscatter response signal 40 that istransmitted back to the interrogator 32. The response signal 40 caninclude an identification code stored in memory 50, or other data. WhileFIG. 3 shows only two tags 44, there could be one or multiple tags 44 inuse, capable of communicating with the reader 32.

In the embodiment shown in FIG. 3, the RF tag 44 includes an antenna 42coupled to a modulator defined by processor 48. The tag 44 includes aswitch coupled between the antenna 42 and processor 48. In theembodiment of FIG. 3, the switch is included in the processor 48.Alternatively, the switch can be a switch external to the processor 48,such as an n-channel MOS transistor, a p-channel MOS transistor, abi-polar transistor, or any of numerous other types of switches.

In FIG. 3, a modulating signal from the processor 48 is input to theantenna 42 to cause the antenna to alternately reflect or not reflect.One item that can be transmitted from the tag to the reader is anidentification code that is stored in memory 50 of the RF tag 44. In oneembodiment, after receiving a command, the reader sends a carrier waveor interrogation signal 36 that is received by the antenna 42, and thatsignal is selectively reflected or not reflected back by the antenna 42by the tag 44 shorting or not shorting dipole halves of the antenna 42to produce portions of the response signal 40 (backscattercommunications). Other communication methods are possible.

It will be appreciated that the depiction of the RF tag 44 in FIG. 3 isone embodiment only; RFID tags are well-known in the art. For example,U.S. Pat. No. 4,075,632 to Baldwin et al., which is incorporated hereinby reference, discusses in detail circuit structures that could be usedto produce the RF tag 44, if modified as described below.

Similarly, the internal structures of the interrogator 32 are not shownin FIG. 3.

For example, the interrogator 32 can be the receiver described in U.S.Pat. No. 4,360,810 to Landt, which is incorporated herein by reference,modified as described below.

In the illustrated embodiment, the reader 32 includes a processor 54,which in turn includes an arithmetic logic unit (ALU) 56 and a randomnumber generator 58. The processor 54 further includes a memory 64;alternatively, the reader 32 includes a memory separate from theprocessor 54. The memory 64 can store a secret key value 68, the use ofwhich will be described in greater detail below. The memory 50 of eachtag 44 can also store a secret key value 66 which, in the illustratedembodiment, is the same value as the key value 68.

The processor 54 includes other features typically included inprocessors of the type typically employed in RFID readers. In oneembodiment, the random number generator 58 actually generates pseudorandom numbers; i.e., the numbers generated may follow a pattern thatcould be recreated. While the random number generator 58 is shown asbeing separate from the ALU 56, in one embodiment, the random numbergenerator 58 is defined in part by the ALU 56. Similarly, each of the RFtags 44 is shown as including an arithmetic logic unit (ALU) 60 and arandom number generator 62. Depending on whether the tags 44 or thereader 32 will be the authenticator (as will be described below), therandom number generator may be omitted from either the RF tags 44 orfrom the reader 32.

FIG. 4 is a flowchart illustrating steps performed in an embodiment bythe tag and reader of FIG. 3, which tag and reader can be in coupleddevices according to the present invention. Aspects of the inventionthat will be described in connection with FIG. 4 can be embodied inmethods and apparatus employing tags of varying levels ofsophistication. Multiple IF frequencies or read-while-write capabilityare not required. An advantage is that the amount of communicationbetween the reader and the tags is minimized. This is useful to increasethe speed of discovering or verifying the identities of tags.

Aspects of the invention described in connection with FIG. 4 alsoprovide authentication (identity verification) over a public, openchannel. This method can be used by the tag to authenticate the reader,or by the reader to authenticate the tag.

All participants in the authentication perform long, logicalmathematical operations. More particularly, in step S1, the Requestordevice requesting access (can be either a tag or the reader) sends amessage to the Authenticator. In one embodiment, the Requestor is a tag44 and the Authenticator is the reader 32. In another embodiment, theRequestor is the reader 32 and the Authenticator is a tag 44. In theembodiment of the claimed invention, it is contemplated that theRequestor is the reader and is a component of a portable electronicdevice, and the tag is an RF tag that is a remote coupled device.

In step S2, the Authenticator generates an “Access Challenge” number. Inone embodiment, the “Access Challenge” number is a pseudo random numbergenerated by the random number generator 58 or 62. In one embodiment,the “Access Challenge” value is a long binary value, which is randomlygenerated. The length can be 128 bits, 256 bits, 512 bits, or anydesired value selected depending on the desired security level versuscost and processing time.

In step S3, the Authenticator sends the “Access Challenge” number orvalue to the Requestor.

In step S4, the Requestor performs a long mathematical operation (orseries of mathematical operations) on the “Access Challenge” numberbased upon the secret key value 66 or 68 (see FIG. 2) to define a“Challenge Response.”

In step S5, the Requestor replies to the Authenticator with a “ChallengeResponse”.

In step S6, the Authenticator independently computes its own “ChallengeResponse” by performing the same mathematical operation of step S4 thatthe Requestor performed and by using the same key value that theRequestor performed. Step S6 could be performed after step S1 and beforestep S2, simultaneously with step S2, or at any time between step S1 andstep S7.

In step S7, the Authenticator compares the received “Challenge Response”from the Requestor matches the value computed by the Authenticator. Ifnot, the Authenticator denies access in step S8. If so, theAuthenticator grants access in step S9. If the Authenticator deniesaccess, this can be an indication that an RF tag is detected andresponding, but the responding RF tag is not a coupled RF tag for theremote electronic device. In this case, further RF tags in range arelikewise challenged, and if no RF tags transmit the correct challengeresponse, the portable electronic device is completely or partiallydisabled at S8A.

In step S10, the Authenticator can send a message to the Requestorinforming the Requestor that access is granted. After step S10, normalcommunications are enabled in step S11, including transmission ofadditional information, if any, stored in the Authenticator to theRequestor (e.g., identification information, account information,financial information, etc.), and enablement of operation of theportable electronic device 11. Instructions in memory and executableinstructions in the computing device can enable all predeterminedfunctions according to known means in the art, that is, at this point,it is as if an electronic device was turned on and any necessaryauthenticating passwords were properly entered, and the device can beutilized for all enabled functions.

Upon authentication of the remotely coupled RF tag and enablement ofoperations of portable electronic device 11, the process of detecting aremotely coupled RF tag can repeat itself at predetermined intervals,S12. The predetermined intervals can be from a range of once everymillisecond to once every half hour, the range including everymillisecond interval in between.

Thus, one minute, two minutes, ten minutes, and every other multiple ofmilliseconds between one and half an hour, are literally disclosedherein.

The advantages of approach illustrated above include:

(1) The “Access Challenge” number is a generally random number, therebyhelping to ensure security of the portable electronic device.(2) The response to the Access Challenge is dependent upon the Challengevalue, but is convoluted to obscure the key value.(3) Multiple key values are possible, which can uniquely identify the RFtag.(4) The length of the keys and challenge values can be configured to thesecurity requirement at hand. Tradeoffs can be made between level ofsecurity and system cost. Greater security requires longer keys, longermessages, and more processor power.(5) The approach of FIG. 4 can be used to generate encryption values fora data stream, in an alternative embodiment. The challenge response isnot transmitted, but is used to encrypt the data stream.

The above approach can be implemented in a passive or semi-passive RFIDapplication to provide a level of security and/or data encryption notpresently available. The passive or semi-passive RFID application willrequire that the Authenticator initiate all communication processes withthe Requestors. Various embodiments of the invention could be employedin security and inventory management applications.

In another embodiment, public key encryption can be used. Readerauthentication occurs as follows. The reader requests to read or writetag data. The tag responds with a challenge value (random number). Thereader encrypts the challenge value using its private key. The readersends the encrypted challenge response to the tag. The tag uses thereader public key to decrypt the challenge response. The tag comparesthe results to the original challenge value and, if there is a match,the reader is authenticated.

The process for a tag authentication is as follows. The reader issues arequest to a tag including a non-encrypted challenge value. The tagencrypts the challenge value using its private key, creating a challengeresponse. The tag sends the challenge response to the reader (no key issent). The reader decrypts the challenge response using the known tag'spublic key. If the reader-computed result matches the original challengevalue, the tag is authenticated.

In another embodiment related to those just described, both a tag and areader function to authenticate the other. For example, a reader sends anon-encrypted first challenge value to a tag. The tag encrypts the firstchallenge value using a tag private key and sends it to the reader, as afirst response, along with a non-encrypted second challenge value. Thereader decrypts the first response using a tag public key, and comparesthe result with the non-encrypted first challenge value. If thecomparison is valid, then the tag is determined to be authentic. Thereader then encrypts the second challenge value using a reader privatekey and sends it to the tag as a second response. The tag then decryptsthe second response using a reader public key, and compares the resultwith the non-encrypted second challenge value. If the comparison invalid, then the reader is also determined to be authentic. The tag andthe reader may now continue with the exchange of data or commands.

In the embodiments just described above, it is assumed that both thereader and the RF tag(s) know the public key or keys of the other, inadvance of the authentication process. This is a valid assumption ifboth (all) belong to the same system, in the control of the same user.In addition, multiple keys (public and private) may be used to realizecorresponding level of security. Generally, the longer (i.e., morecomplex) the key length, the greater the level of security within theexchange. In the example just described, the non-encrypted first andsecond challenge values may be the same; responses would be differentdue to different private keys. Other embodiments using public andprivate keys are also possible.

Any design of RF tag can be used for security purposes. The addition ofauthentication capability described above provides an additionalmechanism against spoofing. The security needs are many, with potentialtheft being high on the list. The traditional means of detecting when atheft has occurred is to track inventory. Items can be identified asthey are removed from a monitored area or when subsequent inventoriesare made of the storage location.

Thus, methods and apparatus for authenticating reader or tags over apublic, open channel have been provided. A system has been provided thatis more robust against spoofing and other illicit access attempts thanpassword-based methods.

However, other methods for authenticating readers can be utilized. Forexample, the system described in U.S. Pat. No. 7,806,325, issued Oct. 5,2010 to O'Brien et al., and hereby incorporated by reference herein, canbe utilized. In the O'Brien system, a signature is obtained from acontactlessly readable tag, such as the remote coupled RF tag of thepresent invention. The signature is decrypted to obtain a candidateidentifier and a scrambling code associated with the signature. Aremotely coupled RF tag can be identified by validating the candidateidentifier based on at least one of the scrambling code and thesignature. Once identified, the remote electronic device can becompletely or partially enabled for use.

In another method for authentication, the present invention can utilizethe system described in U.S. Pat. No. 7,450,010, issued Nov. 11, 2008 toGravelle et al., and hereby incorporated by reference herein. TheGravelle method is a protocol for preserving the privacy ofcommunications between an RFID reader (such as in a portable electronicdevice) and an RFID tag (such as the remotely coupled RF tag of thepresent invention). Two distinct actions are taken. First, the readerand the tag must be mutually authenticated as being authorizedparticipants in the communications. This mutual authentication can beachieved as described in Gravelle by a user of a portable electronicdevice and at least one coupled RF tag. For example, the portableelectronic device can “find” and “program” an RF tag under the rightfuluser's control, much as Bluetooth devices are activated today. Afterthat process is successfully completed, the authenticity of eachauthorized participant must be validated prior to each subsequentcommunication between reader and tag.

In an embodiment, the present invention can utilize the system forutilizing parametric reradiated technology, as disclosed in U.S. Pat.No. 7,498,940, issued Mar. 3, 2009 to Pettus, and hereby incorporated byreference herein. The Pettus system can encode and decode information byuse of radio frequency antennas. The system includes one or moreinterrogator devices and RFID data tags. The RFID data tags include aplurality of antenna elements which are formed on a substrate ordirectly on an object. The antenna elements are oriented and havedimensions to provide polarization and phase information, whereby thisinformation represents the encoded information on the RFID tag. Theinterrogator device scans an area and uses radar imaging technology tocreate an image of a scanned area. The device receives re-radiated RFsignals from the antenna elements on the data tags, whereby the datatags are preferably represented on the image. The re-radiated RF signalspreferably include polarization and phase information of each antennaelement, whereby the information is utilized using radar signal imagingalgorithms to decode the information on the RF data tag. Such technologycan find use in electronic devices that support radar technology.

In an embodiment, the present invention can utilize the cryptographictechniques taught in U.S. Pat. No. 7,532,104, issued May 12, 2009 toJuels. Such cryptographic techniques permit implementation ininexpensive radio frequency identification (RFID) tags or other RFIDdevices. In an RFID system comprising one or more RFID devices (such asremote coupled RF tags) and at least on reader (such as a readercomponent of a portable electronic device) that communicates with thedevices, a plurality of pseudonyms is associated with a given one of theRFID devices. The pseudonyms can be predetermined or set by the user ofthe portable electronic device and RF coupled device. The RFID devicetransmits different ones of the pseudonyms in response to differentreader queries, and an authorized verifier is able to determine that thedifferent transmitted pseudonyms are associated with the RFID device.

RF tags of the present invention can be made in any way known in theart, and can be made according to the method disclosed in U.S. Pat. No.7,636,044, issued Dec. 22, 2009 to Callaghan. RFID tags can be made inconjunction with an industrial controller to facilitate RFID tagprinting and application of the RFID tags to manufactured items.

Systems of the present invention including an electronic device such asa smart phone and a coupled RFID tag can be made utilizing thetechnology enabled and disclosed in U.S. Pat. No. 7,148,803, issued Dec.12, 2006 to Bandy et al. and its divisional and continuation patents andapplications, each of which are incorporated by reference herein. Inparticular, the present invention can be made according to the teachingsof the '803 patent as embodied in the technology currently available inthe GT-601 NFC RFID Sensor Cell Phone manufactured by GENTAG, Inc.,Washington D.C., USA, and RFID sensors also available from GENTAG, asdisclosed at www.gentag.com.

Therefore, the present invention can be made by adapting the GENTAG,Inc. technology as enabled by GENTAG's patents and patent applicationsas well as by adapting GENTAG's off the shelf technology including RFIDsensors, RFID diagnostic technology, including GENTAG's skin-patchtechnology. Adaptation by one skilled in the art can include adaptingthe device architecture, software, firmware, memory, or other componentsas necessary. For example, the skilled person can modify the wirelesssensor reader disclosed at paragraph [0076] of US 2009/0212918 A1, whichis a continuation application of the above-mentioned '803 patent, and,as mentioned above, is incorporated by reference herein. As disclosed in'918 the wireless sensor (which can be a portable electronic device asdisclosed in this specification) reader can include an alarm forindicating when certain thresholds are reached or certain conditions aredetected by an RF addressable sensor. In the present invention, ratherthan sound an alarm, the wireless sensor reader can have executableinstructions in memory that cause the wireless sensor reader to bepartially or completely disabled when the condition detected is, forexample, the absence of a received signal from the RF addressablesensor.

In another embodiment, the invention can include additional loss andtheft protection against unauthorized use of both the portableelectronic device and the remote coupled device. It is foreseeable thata thief, for example, would in addition to stealing the portableelectronic device also steal the authorized user's remote coupleddevice, which can be an RF addressable sensor, such as an RFID tag.

In an embodiment, the RF addressable sensor can be worn in closeproximity to the authorized user's body in a manner that causes theportable electronic device to be disabled if the RF addressable sensoris removed from such proximity. In one embodiment, for example, the RFaddressable sensor, such as an RFID tag can be embedded in, joined to,attached to, or otherwise disposed on a belt, bracelet, necklace, orother piece of clothing/jewelry such that removal of the clothing orjewelry destroys the RF addressable sensor, or otherwise renders the RFaddressable sensor inactive. For example, a bracelet on which a coupledRFID tag is disposed can have an electrically conductive strip thatcompletes a circuit when the bracelet is properly worn, and which, uponremoval forces a break in the circuit, which in renders the RFaddressable sensor inoperative or results in disablement of the portableelectronic device or both. In this manner, if a thief were to steal aSmartphone and RFID tag coupled according to the present invention, theSmartphone could be disabled upon forced removal of the user's RFIDbracelet. Of course, the same principle can be varied with differentpieces of clothing or jewelry and with different technology, in waysknown in the art. In an embodiment, for example, the RF addressablesensor can be adhered to a piece of clothing or jewelry such that uponremoval the RF addressable sensor itself is destroyed, such as bytearing.

In another example, a bracelet, such as a paper or plastic strip havingadhesive on one or both ends can be formed such that an RFID tag isdisposed on or near a point of attachment, e.g. on or near the adhesive.The bracelet can be positioned around a wrist, ankle, forearm, or othersuitable body part with one end being joined to another portion of thepaper strip in a position to make the bracelet snug enough not to falloff. To remove the bracelet, the adhesive joint can be broken, which canin turn destroy the RFID tag, thereby destroying the RFID taginoperative. In this manner, the RFID tag must be destroyed to removethe bracelet, thereby ensuring that even if a thief steals theelectronic device and tears off the bracelet, the electronic devicewould be partially disabled, disabled, or otherwise inoperable.

Such paper or plastic strips having disposed thereon an RFID tag can bemass produced on rolls, such that a user can simply remove one each day,week, month, or other suitable time period, for wearing. The rolls canbe formed from a strip of paper or plastic in which RFID tags arejoined, such as by printing or adhesive, in predetermined intervals,including intervals of from about 2 inches to 24 inches, or from about 3inches to about 18 inches, or from about 4 inches to about 12 inches, orfrom about 5 inches to about 10 inches, or any other range within any ofthe above ranges. Likewise, the strip can have perforations, or otherlines of weakness to facilitate easy removal of one length which caninclude at least one RFID tag. In an embodiment, an RFID tag is disposednear, for example, within about 0.25 inches to about 5 inches, or fromabout 0.5 inches to about 3 inches, or from about 0.5 to about 1.5inches from one of the lines of weakness.

Another way to ensure that an authorized user's remote coupled devicecould not be stolen and used with the authorized user's portableelectronic device would be to have the remote coupled device alsomeasure and detect at least one of the authorized user's biometrics. Bybiometrics is meant measurable parameters from a user's body, such astemperature, blood glucose level, and other biomarkers.

In one embodiment, the portable electronic device can be coupled to aremote coupled device that is an RFID sensor capable of measuringtemperature. The RFID sensor can be in the form of a skin-proximitybracelet or necklace, or a patch, such as the GENTAG smart skin patchavailable from GENTAG. In one embodiment, the user can utilize theGENTAG GT-202 Smart Wireless Fever Monitoring Skin Patch. The GT-202 iscompatible with Near Field Communication (NFC) cell phones, PC's andother electronic devices, can have a unique ID, can be adhesivelyattached and worn for one to two weeks, and can be programmed fortemperature logging functions, measuring temperature with 0.1 Caccuracy. When used with the present invention, temperature monitoringRFID tag, such as the GT-202 can be monitored by the portable electronicdevice. As long as the RFID tag is in close proximity to the authorizeduser's skin, the portable electronic device can measure at periodicintervals, such as intervals ranging from 0.1 seconds to 10 minutes andevery one-tenth second interval in between. If the RFID tag experiencesa temperature change, such as a decrease in temperature associated withbeing removed from the user's skin, the reported decrease in temperature(or other change) could initiate executable instructions in memory thatcause the Smartphone to be disabled when the temperature changecondition is detected.

Therefore, in one embodiment, the present invention can be described asa portable electronic device being dependently operable upon a remotecoupled device, wherein the remote coupled device can be an RFaddressable sensor, wherein the RF addressable sensor can be an RFIDdevice capable of measuring and transmitting to the portable electronicdevice temperature, wherein operation of the portable electronic devicefor at least a portion of its intended use is dependent on being inproximity to the remote coupled device measuring a temperature within apredetermined temperature range.

Various additional embodiments for RF tags, RF addressable sensornetworks, RF addressable sensors, and RF addressable sensor readers aredescribed in the following subsections. These embodiments are providedfor illustrative purposes, and it should be understood that theinvention is not limited to the particular embodiments described below.Alternative embodiments for RF addressable sensor networks, RFaddressable sensors, and RF addressable sensor readers will be apparentto persons skilled in the relevant arts based on the teachings herein,including those with equivalents, combinations, modifications, greateror fewer components, etc. It is to be understood that such alternativeembodiments are within the scope and spirit of the present invention.

FIG. 5 is a block diagram of an illustrative RF addressable sensornetwork 100 for monitoring, detecting, and geolocating RF addressablesensors, according to an embodiment of the present invention. Network100 includes a population of RF addressable sensors 102, one or morewireless addressable sensor readers (or, as above, interrogators) 140,and a communications network 180. In an embodiment of the presentinvention, communications network 180 is a publicly accessiblecommunications network. In another embodiment, communications network180 is a private network or a hybrid network including public andprivate portions. Communications network 180 includes a wirelesscommunications network 170 and/or a data communications network 175.While FIG. 5 depicts communications network 180 as including a wirelessand a data communications network, persons skilled in the relevantart(s) will recognize that other network architectures could be usedwith the present invention.

In an embodiment, end user devices (or, as above, portable electronicdevices) 182 may be coupled to communications network 180. End userdevices 182 can include logic for bi-directional communication with thecommunications network 180. End user devices 182 may be present toinitiate a request for sensor data from RF addressable sensors 102 bymaking the request to readers 140 over network 180. In an embodiment,end user devices 182 also include logic to process received sensor data.For example, a user device 182 may include features of a processor 190,which is further described below. Thus, in an embodiment, a user device182 may both initiate a request for sensor data and receive and processthe resulting sensor data. End user devices 182 can communicate withcommunications network 180 via a wireless link 184 or a wired link 186.In an alternate embodiment, network 100 also includes a sensor networkprocessor 190.

According to embodiments of the present invention, the population of RFaddressable sensors 102 may include any number of one or more RFaddressable sensors 110. RF addressable sensors 110 integrate RFID tagfunctionality and sensor functionality. RF addressable sensor 110 may beattached to the exterior of an item, inserted into an item (e.g.,immersed in a liquid), may be adhered to a wearer's skin, or may bestand-alone.

Wireless sensor reader 140 includes logic to interrogate the populationof RF addressable sensors 102 and logic to read sensor data and RFID tagdata transmitted by the RF addressable sensors 110. In an embodiment,wireless sensor reader 140 also includes logic to process the receivedsensor data. Wireless sensor reader 140 can be any wireless devicecapable of communicating via an air interface protocol with thepopulation of RF addressable sensors 102. In embodiments of the presentinvention, wireless sensor reader 140 could be a wireless phone, apersonal digital assistant (PDA), a computer having wirelesscommunications capabilities, or other type of mobile, handheld, and/orcomputing device.

According to the present invention, signals 115 are exchanged betweenthe wireless sensor reader 140 and the population of RF addressablesensors 102 according to one or more protocols. Signals 115 are wirelesssignals, such as radio frequency (RF) transmissions. In an embodiment ofthe present invention, reader 140 and the population of sensors 102communicate via a single protocol for both RFID tag communications andsensor communications. In an alternate embodiment, reader 140 and thepopulation of sensors 102 communicate via a first protocol for RFID tagcommunications and via a second protocol for sensor communications.Examples of protocols used for RFID tag communications are described inthe following co-pending U.S. patent applications, each of which isincorporated by reference in its entirety: application Ser. No.10/072,984, filed Feb. 12, 2002, entitled “Radio FrequencyIdentification Architecture;” application Ser. No. 10/687,690, filedOct. 20, 2003, entitled “Method for the Efficient Reading of aPopulation of Radio Frequency Identification Tags with UniqueIdentification Numbers Over a Noisy Air Channel;” and application Ser.No. 10/693,687, filed Oct. 27, 2003, entitled “Optimization of a BinaryTree Traversal with Secure Communications.” The present invention isalso applicable to any other types of communication protocols betweentags and readers otherwise known or yet to be developed.

In an embodiment of the present invention, signals 165 are exchangedbetween the wireless sensor reader 140 and the wireless communicationnetwork 170 according to one or more protocols. Signals 165 aretypically RF signals. As can be appreciated by a person skilled in therelevant art(s), the communications protocol used between reader 140 andwireless network 170 can be any wireless air interface protocol, such asused in IS-41 or GSM wireless communications networks, for example.

In an alternate embodiment, wireless sensor reader 140 can alsocommunicate to the data communications network 175 via interface 185.Interface 185 is a wired interface. For example, when wireless sensorreader 140 is a computer having wireless capabilities, sensor reader 140may access the Internet via interface 185 using TCP/IP. As can beappreciated by a person skilled in the relevant art(s), thecommunications protocol used between reader 140 and data communicationsnetwork 175 can be any data communications protocol.

In an embodiment of the present invention, wireless network 170 is apublicly accessible network, such as a switched telephone networksupporting wireless communications. In an alternate embodiment, wirelessnetwork 170 may be a private network. Wireless network 170 may becoupled to a publicly accessible data communications network 175.Publicly accessible data communications network 175 can be a publicswitched telephone network or a public data network such as theInternet. In addition, data communications network 175 can be connectedto other public or private networks as would be appreciated by personsskilled in the relevant art(s).

Sensor network processor 190 receives sensor data over network 180, andprocesses the data. Furthermore, in an embodiment, processor 190transmits the processed data back over network 180 to reader 140, forexample. Sensor network processor 190 includes a geolocation processor192 and a sensor data processor 194. Sensor network processor 190 may bea stand-alone system or may be distributed across multiple systems.Geolocation processor 192 includes logic to receive data from one ormore RF addressable sensors 110 and to perform GPS and/or non-GPSgeolocation of the RF addressable sensors 110 based on the received dataand/or signals. In GPS based geolocation, location is determined usingsignals provided to wireless sensor readers 140 via geo-stationarysatellites. A limitation of GPS based geolocation is that signals arenot available if the device is shielded (e.g., underground, in abuilding, etc.). In non-GPS based geolocation, location is determined bytriangulation based on transmission systems as reference points (e.g.,mobile base stations) and time to signal calculations. In this manner,cell phone towers can geolocate wireless sensor readers 140 throughcalculations done by processor 190. Similarly, wireless sensors readers140 may be used as a basis to identify the precise location ofindividual sensors 110 by triangulation and synchronization of internalclocks. Since either the location of cell phone towers and/or wirelesssensor readers is usually known and can include GPS coordinates, precisegeolocation of sensors can be achieved using either GPS, non-GPS orhybrid systems.

For more information concerning geolocation, see U.S. Pat. No.6,031,454, filed Nov. 13, 1997, entitled “Worker-Specific ExposureMonitor and Method for Surveillance of Workers,” which is incorporatedherein by reference in its entirety.

Sensor data processor 194 includes logic to receive sensor data from oneor more RF addressable sensors 110, perform processing on the receiveddata, and communicate information based on the processing to wirelessreader 140 or an end user device 182. Sensor network processor 190 iscoupled to the wireless communications network 170 and/or the datacommunications network 175.

FIG. 6 is a block diagram of a radio frequency (RF) addressable sensor210, according to an embodiment of the present invention. RF addressablesensor includes RFID tag functionality integrated with sensorfunctionality.

Radio frequency addressable sensor 210 includes an integrated circuit222, a plurality of RF pads 204 a through 204 n, and a plurality ofantennas 206 a through 206 n. These components are mounted or formed ona substrate 202. RF addressable sensor 210 also includes a plurality ofsensor elements 291 a-291 n, 292 a-292 n, and 294 a-294 n.

Sensor elements may be included in integrated circuit 222, on substrate202, external to substrate 202, or in any combination of the above. Asshown in FIG. 2, sensor elements 291 a-n are included as a component inintegrated circuit 222. Sensor elements 292 a-n are included on thesubstrate 202. Any sensor element that is compatible with thefabrication of RF addressable sensor 210 can be used. In an embodimentof the invention, sensor elements 292 a-n can be thin film sensorelements that are deposited, printed, or directly assembled ontosubstrate 202. Sensor elements 294 a-n are external to the substrate202. If the sensor element is located on the substrate (collectivelysensor elements 292) or external to the substrate (collectively sensorelements 294), the sensor element will be coupled to one or more of theplurality of sensor pads 208 a through 208 n (collectively sensor pads208).

The structure of sensor pads 208 depends on the type of sensor elementcoupled to the sensor pad 208. In an embodiment of the presentinvention, sensor pads 208 are metal. However, certain biological sensorelements consist of soft materials. When coupling to metal sensor pads208, the potential exists for these sensor elements to be pierced. In analternate embodiment of the present invention, one or more sensor padsare soft sensor pads. These soft sensor pads provide a transition from ametal connection layer for coupling to the integrated circuit componentsto a soft connection layer for coupling to the sensor element. By usinga soft transition method any type of external sensor element can becoupled to substrate 202. For example, doped inks or conductive polymerscan be used to couple and bond substrate 202 to an integrated sensor asdescribed below. The integrated sensor may be fabricated using othermicro or nanofabrication techniques, thereby providing a means for ansophisticated integrated wireless sensor to be produced at a very lowcost and for many different market applications.

Because of this flexible architecture, various types of sensor elementscan be implemented in RF addressable sensor 210. An RF addressablesensor 210 may include only one type of sensor element or may include acombination of different types of sensor elements. Examples of sensorelements include: gas sensor elements that detect the presence ofchemicals, such as those associated with drugs or precursor or tracechemicals of explosives such as Pentaerythritol Tetranitrate (PETN) andHexahydro-1,3,5-triazine (RDX); temperature sensor elements thatgenerate information indicating ambient temperature; accelerometers thatgenerate information indicating movement or vibration; optical sensorelements that detect the presence (or absence) of light; pressure sensorelements that detect various types of mechanical pressures; tampersensor elements that detect efforts to destroy or remove the sensor fromaffixed items; electromagnetic field sensor elements, radiation sensorelements; and biochemical sensor elements. However, this list is notexhaustive. RF addressable sensor 210 may include other types of sensorelements or combinations thereof, as would be apparent to personsskilled in the relevant art(s).

Sensor elements 291 a to 291 n are sensors that can be fabricateddirectly on the chip surface as part of integrated circuit 222. Forexample, these include sensors for temperature change, radiation,electrical changes, field effects and motion. Sensor elements 292 a to292 n may be a number of different sensor types such as a chemicalsensors, biological sensors, etc. In an embodiment, sensor element 292 amay include of a plurality of special thin film elements such aspolymers. For example, in chemical sensor elements, chemicals present inthe air are absorbed differently by each of the thin film elements,changing the resistance of each and creating a characteristic electronicsignature. Because many types of detectors can be added, this technologycan be designed to recognize a wide range of chemicals. It should benoted that hybrid systems are also possible. For example, embeddedpassives may be used to create some of the electronic functionality onthe chip and combined with sensor functionality.

In an alternate embodiment, one or more of the antennas 206 may be usedas sensor elements. For example, the antenna could operate as an on-offsensor. As the antenna absorbs material to be sensed, the antennabecomes detuned and the tag stops operating. Thus, when the tag shutsoff, the material has been sensed. In this embodiment, the antennasacting as sensor elements are coupled to both an RF pad 204 and a sensorpad 208. In an alternate embodiment, RF pads 204 are coupled to both theRF power and communications interface 240 and the sensor interface 250.

In an embodiment of the present invention, RF addressable sensor 210 isor includes a micro-electro-mechanical system (MEMS). In an embodiment,sensor elements can include mechanical and electromechanical devices“micromachined” on a common or separate substrate with the remainingcomponents of the RF addressable sensor 210. In this embodiment, theremaining electronic components could be fabricated using conventionalintegrated circuit technology. For example, in a MEMS RF addressablesensor, one or more sensor elements can contain microcantilever devices.

In an alternate embodiment, the sensor elements 294 a-294 n are externalto substrate 202 and can be fabricated using MEMS technology andattached to substrate 202, while the components included on substrate202 can be fabricated using conventional technology. This allows anytype of sensor to be coupled with an RFID tag.

FIG. 6A is a block diagram of an RF addressable sensor 210 having anexternal sensor element according to embodiments of the presentinvention. External sensor element 294 may be coupled to an independentpower supply 293. Substrate 202 may also or alternatively be coupled toindependent power supply 293. In an embodiment, power supply 293 is adisposable battery or a photovoltaic cell. Thus, sensor element 294 doesnot require periodic “power” signals from the wireless reader. In anembodiment, sensor element 294 includes a memory.

An advantage of the RF addressable sensor configuration of FIG. 2A isthat the wireless components and geolocation features can be provided bythe RFID tag and cell phone combination thereby reducing the cost andmaking it suitable for sensor networks. An example of an application isa homeland security network with sensors that are dispersed by airplaneover certain areas together with low cost readers. If a hazard isdetected, sufficient power is present at the sensor level to send a“wake up” signal to a nearby reader. The reader then geolocates itselfand the sensor and relays the information to a remote processor 190.Cross validation of sensor events may then be achieved by activating andreading other sensors in the same geographical area. A further advantageis that the present invention can be used in combination with sensorsthat require more power than is available on an RFID tag. In addition,sensor elements that require very different manufacturing processes thanthe RFID tag can also be used in the present invention.

In an embodiment of the present invention, as shown in FIG. 6, RFaddressable sensor 210 optionally includes a plurality of referenceelements 295 a-295 n, 296 a-296 n, and 297 a-297 n. Similar to thesensor elements, reference elements may be included in integratedcircuit 222, on substrate 202, external to substrate 202, or in anycombination of the above. As shown in FIG. 2, reference elements 295a-295 n are included in integrated circuit 222; reference elements 296a-296 n are included on substrate 202; and reference elements 297 a-297n are external to substrate 202. A sensor element need not have areference element. If the reference element is located on the substrate(collectively reference elements 296) or external to the substrate(collectively reference elements 297), the reference element will becoupled to one or more of the plurality of reference pads 209 a through209 n (collectively reference pads 209).

Reference elements allow for the cross validation of sensor data andestablish baselines. This is important for chemical measurements, forbiological sensors, and for any sensor situation where there are two ormore variables and at least one of the variables is dependent orproportional to the other.

In an embodiment of the present invention, a sensor element may have aplurality of associated reference elements. In an embodiment, areference element provides a baseline and/or calibrated value to which asensor element can be compared either internally or externally. In anembodiment, reference data can be transmitted by the RF addressablesensor to the wireless sensor reader or to the network sensor processorfor calibration of the sensor elements.

As shown in the embodiment of FIG. 6, integrated circuit 222 includes aRF power and communications interface 230, a sensor interface 250, andan RFID control module 240. Sensor interface 250 includes a digitizer oran analog to digital converter (ADC) 252. ADC 252 receives analogsignals from sensor elements and converts the analog signal into acorresponding digital signal. ADC 252 can be coupled directly to sensorelements implemented in integrated circuit 222 and is coupled to othersensor elements 292 and 294 via sensor pads 208. In an embodiment, afilter (not shown) may be used between the sensor element and ADC 252.

In an embodiment of the present invention, sensor interface 250optionally includes one or more thermistors 254. Thermistor 254 is adevice that has an electrical resistance that varies predictably withtemperature. Thermistor 254 provides a correlation point for dataobtained from a sensor element. Because temperature is a generally knownvariable, including a thermistor in RF addressable sensor 210 allows thesensor 210 to use temperature as a basis for comparison or allows asensor element output value to be adjusted based on temperature. Thisadjustment can occur internally or externally at the wireless sensorreader 140, end user device 182, and/or network sensor processor 190.

In an embodiment of the present invention, thermistor 254 is made of amaterial such as a metal-oxide that has a resistance that changes in alinear fashion according to temperature. Hence, at a given temperature,the thermistor has a certain value that can be correlated precisely to agiven temperature. The calibration of thermistor 254 can be done inbatches after the chip is microfabricated. Calibration can be achievedby bringing the chip to a set temperature and programming into the chipthe corresponding value. This process can be repeated at two differenttemperatures, thereby providing the reference in memory.

In an embodiment of the present invention, thermistor 254 is made of anon-linearly changing material. In this embodiment, additionalcalibration points are used. As would be appreciated by persons skilledin the relevant art(s), other implementations of thermistor 254 can beused in the present invention.

In an embodiment, sensor interface 250 may optionally include a memory256. Memory 256 stores information used by RF addressable sensor 210 toprocess sensor data received from sensor elements. The information maybe stored permanently or temporarily. In an embodiment of the presentinvention, memory 256 is a programmable memory. The stored informationmay be used internally by the RF addressable sensor 110 or may becommunicated for use externally by the wireless sensor reader 140, anend user device 182, and/or the network sensor processor 190.

In an embodiment, memory 256 stores a sensor data table 258. The sensordata table 258 is configured to store data related to all or a subset ofsensor elements supported by the RF addressable sensor 210. For example,the sensor data table may store a sensor element identification number,a preferred read time, spacing interval between reads, and/or sensorelement specific data for all or a subset of sensor elements.

Using this approach a universal sensor platform is created based on RFIDtechnology by allowing wireless devices such as phones to become “smart”sensor reader devices. In an embodiment, a wireless device such as aphone is modified to include RFID-sensor tag reader functionality, asdescribed herein. In an embodiment, when a sensor 110 having data table258 is activated by wireless sensor reader 140, the sensor 110identifies itself (e.g., by providing its identification number) and canprovide the cell phone reader with the necessary information foranalyzing the sensor output. In an embodiment, sensor data table 258also includes sensor handling information that is communicated to reader140. For example, if sensor 110 is to detect a specific allergen infood, a complete step-by-step testing protocol can be provided and canbe displayed directly on the screen of the phone or reader device 140.In another embodiment, some or all of the necessary information tohandle and analyze the sensor is retrieved from processor 190.

Software may also be downloaded directly and transparently into the cellphone or reader 140 to “train” the wireless device to recognize andanalyze that given type of RFID-sensor. This information may be storedpermanently or temporarily in wireless device 140. When the necessaryprocessing and analysis information is downloaded from a remotelocation, only the ID of the RFID-sensor is necessary, providing ahighly streamlined solution for universal sensor analyses for wirelessdevices such as cell phones. In another embodiment, hybrid systems canbe provided whereby only a basic sensor analysis protocol can bedownloaded into the cell phones and the sensor data processing is doneremotely. This situation is particularly applicable where complexmultivariate analyses of sensor data are required. Phones may alsoinclude in permanent memory a summary table with the necessary IDs torecognize any type of sensor. The above described method allows anordinary wireless device to instantly become a “smart” device for anytype of sensor

Integrated circuit 222 can accommodate multiple antennas 206 a through206 n. This allows RF addressable sensor 210 to have a variety ofantenna configurations on substrate 202. For example, wireless sensorreader 140 (shown in FIG. 1) may operate at a different frequency orhave different directivity than conventional RFID readers. Therefore, RFaddressable sensor 210 may have one or more antennas configured tocommunicate with a conventional RFID reader and one or more antennasconfigured to communicate with wireless sensor reader 140.

The RFID control module 240 controls RF communications between the RFaddressable sensor 210 and wireless sensor reader 140. RFID controlmodule includes a controller 242 and a memory 246. Controller 242includes RFID tag logic 244 to respond to RFID tag interrogation andread communications by the wireless sensor reader 140 or another tagreader and logic to control the operating state of the RFID tagcomponents of the RF addressable sensor. For more information concerninginterrogation of tags, and more generally, communication between an RFIDreader and a population of tags in accordance with an embodiment of thepresent invention, see U.S. Pat. No. 6,002,344, entitled, “System andMethod for Electronic Inventory” which is incorporated herein byreference in its entirety, and the following co-pending U.S. patentapplications, each of which is incorporated by reference in itsentirety: application Ser. No. 09/323,206, filed Jun. 1, 1999, entitled“System and Method for Electronic Inventory”; application Ser. No.10/072,855, filed Feb. 12, 2002, entitled “Method, System and Apparatusfor Binary Traversal of a Tag Population” (Publication No. 0149481-A1);and application Ser. No. 10/073,000, filed Feb. 12, 2002, entitled“Method, System and Apparatus for Communicating with a RFID TagPopulation.”

Controller 242 may optionally include sensor processing logic 245 toprocess sensor data obtained by sensor elements. Memory 246 storesinformation used by the RF addressable sensor when operating as a RFIDtag. Memory 246 may be separate or integrated with memory 256 of thesensor interface. The information may be stored permanently ortemporarily. Memory 246 stores the tag identification number for the RFaddressable sensor 210. In an embodiment of the present invention, thetag identification number indicates the type of sensor elements includedin the RF addressable sensor 210.

RF Power and Communications Interface 230 includes a communicationsmodule 232 and a power generation module 236. Communications module 232is coupled to antennas 206 to provide bi-direction communication with awireless RF addressable sensor reader. In an alternate embodiment,communication module 232 provides bi-directional communication with aconventional RFID reader in addition to the wireless RF addressablesensor reader. In an embodiment, power generation module 236 providesintegrated circuit 222 with an operational voltage based on the RFenergy transmitted by wireless sensor reader 140 and received by thecorresponding RF addressable sensor 110. In another embodiment, powergeneration module 236 may also include a battery or other power source.Alternatively, power generation module 236 may only include a battery orother power source. When present, the power source provides theoperational voltage for integrated circuit 222. In addition, the powergeneration module 236 may provide operational voltage for sensorelements 292 a-n and/or 294 a-n. For example information concerningpower generation in an RFID tag, see U.S. patent application Ser. No.10/383,537, filed Mar. 10, 2003, entitled, “Efficient Charge PumpApparatus” which is incorporated herein by reference in its entirety.

In an embodiment, when a power source is present, the RF addressable tagmay include logic to activate the reader when certain conditions aresensed, on the occurrence of a pre-defined event, and/or at pre-definedintervals. As would be appreciated by persons skilled in the art, manyRFID tag communications protocols can be used to activate the readeraccording to the present invention.

Example embodiments for wireless sensor reader 140 are described in thissection. FIG. 7 is a block diagram of a wireless sensor reader 340according to example embodiments of the present invention. Wirelesssensor reader 340 includes a network communications module 342, acontroller 344, a user interface 346, and an RF addressable sensor logicmodule 350. Wireless sensor reader 340 also includes one or moreantennas. Antenna 348 is configured for communication with wirelessnetwork 170. Antenna 348 is included when wireless reader 340 isintegrated with a wireless communications device. In an embodiment ofthe present invention, antenna 348 is also configured for communicationwith the population of RF addressable sensors. Antennas 349 a-n areincluded when antenna 348 does not support communication with thepopulation of RF addressable sensors. In this embodiment, antennas 349are configured to communicate with the RF addressable sensors 110. In analternate embodiment, network antenna 348 can be removed (e.g.,unscrewed) from reader 340 and replaced with an RFID antenna 349 forcommunication with the population of sensors 102. Controller 344includes logic to coordinate and control the operation of the componentsof wireless sensor reader 340. In an embodiment, controller 344coordinates substantially continuous RF communication with sensors 110.Substantially continuous RF communication can be by periodic send andreceive sequences at predetermined intervals which can be from a rangeof once every millisecond to once every half hour, the range includingevery millisecond interval in between. Thus, one second, one minute, twominutes, ten minutes, and every other multiple of milliseconds betweenone and half an hour, are literally disclosed herein.

User interface 346 can provide a mechanism for the user of the wirelesssensor reader 340 to access and interact with sensor information and/orinitiate a read of one or more sensors 110. User interface 346 mayinclude a display and/or keypad for entering data (e.g., the numericalkeypad of a wireless phone). In an alternate embodiment, user interface346 includes a standalone button for initiating sensor reads and/orprocessing. In addition, the wireless sensor reader 340 includes adisplay for displaying data obtained from RF addressable sensors 110. Inan embodiment, the wireless sensor reader 340 also includes an alarm forindicating when certain thresholds are reached or certain conditions aredetected by an RF addressable sensor.

A user may alternatively initiate sensor processing by entering apre-defined sequence of characters via a key pad (e.g., by entering*2222). Alternately, a user could initiate sensor processing byhighlighting or activating an option provided through a display or by apredefined voice command.

Network communications module 342 includes one or more transmitters andreceivers for communicating with the data communications network 175and/or wireless communications network 170. In an embodiment of thepresent invention, wireless sensor reader 340 communicates with wirelessnetwork 170 via network antenna 348. Accordingly, network communicationsmodule 342 includes a wireless interface coupled to the antenna 348. Inan alternate embodiment of the present invention, wireless sensor reader340 communicates with a publicly accessible data communications network175 via a wired connection. In this embodiment, network communicationsmodule 342 includes a wired network interface. If both types ofcommunications are supported, network communications module 342 willinclude both a wireless interface and a wired interface.

RF addressable sensor logic module 350 includes an RF addressable sensorcommunications module 352 and an RFID tag processor 356. Wireless sensorreader 340 communicates with the population of RF addressable sensors102 via either the network antenna 348 or via one or more RFIDantenna(s) 349 a-349 n. If wireless sensor reader 340 communicates withthe population of RF addressable sensors via one or more RFID antenna(s)349 a-n, RF communications module 352 will include one or moretransmitters and receivers coupled to antennas 349. As will beappreciated by a person skilled in the relevant art(s), RFcommunications module 352 may be implemented in hardware, software,firmware, or in combination thereof.

RFID tag processor 356 includes logic to interrogate and read RFID taginformation from RF addressable sensors 110. As will be appreciated by aperson skilled in the relevant art(s), RFID tag processor 356 may beimplemented in hardware, software, firmware, or in combination thereof.

RF addressable sensor communications module 352 can include sensor dataprocessing logic 355 and geolocation processing logic 353. Sensor dataprocessing logic 355 can be configured to request a read of one or moreaddressable sensors 110 based on input from a user, after a certaininterval of time, and/or upon the occurrence of a pre-defined event.Sensor data processing logic 355 is also configured to process receivedsensor data.

Geolocation processor 353 is optional, and when present, includesalgorithms to perform GPS based geolocation and/or non-GPS basedgeolocation. In an embodiment, sensor reader 340 serves as a geolocationbeacon for RFID-sensors in synchrony with other readers. In anembodiment, the antenna serves as a means for directional geolocation ofRFID sensors.

FIGS. 8A-C depict block diagrams of example configurations for awireless sensor reader 440. Each configuration depicts various ways inwhich RF addressable sensor logic module 350 and RFID antennas 349 a-nmay be incorporated into a device 430. Device 430 can be an existingwireless device such as a computer, tablet computer, Smartphone,wireless phone or PDA. In an alternate embodiment, device 430 is adevice designed specifically to support communicating with RFaddressable sensors 110 and with a communications network such as awireless phone network or the Internet.

In FIG. 8A, RF addressable sensor logic module 350 is integrated intodevice 430. In this embodiment, wireless sensor reader 440 communicateswith both the wireless network 170 and the population of RF addressablesensor tags via antenna 448. In an embodiment of the present invention,module 350 is built into device 430. In an alternate embodiment, device430 includes a programmable processor. The logic for module 350 can bedownloaded and stored in the programmable processor. The logic can bedownloaded via the air interface, an infrared port, a data connectionthrough the accessory port, or via any other interface or link capableof transferring data to device 430.

In FIG. 8B, RF addressable sensor logic module 350 is integrated intodevice 430, as discussed in reference to FIG. 8A. However, in thisembodiment, one or more antennas 449 a-n are already included, or addedonto device 430 for communication with the population of RF addressablesensors 102. Note that for this configuration, antenna 448 is optionaland is not included if wireless sensor reader 340 only communicates witha data communications 175 network via a wired connection.

In FIG. 8C, RF addressable sensor logic module 350 is external to device430 and is attached to device 430 via interface 435. For example,interface 435 could be an accessory port, an infrared port, or any otherinterface or port capable of transferring data to and from device 430such as a wireless phone data/software interface. For example, module350 may be a snap-on and/or plug-in module to device 430. Variousantenna configurations are supported with this embodiment. In anembodiment, existing antenna 448 supports communication with both thenetwork 170 and the population of sensors 102. In an alternateembodiment, additional antennas 449 for communicating with thepopulation of sensors 102 are attached to external module 350. Inanother alternate embodiment, additional antennas 449 for communicatingwith the population of sensors 102 are attached to device 430. As wouldbe appreciated by a person skilled in the relevant art(s), otherconfigurations for wireless sensor reader 440 are possible.

FIG. 9 is a flowchart of a method 500 for RF addressable sensor readcommunications from the perspective of a wireless sensor reader. Method500 will be described with continued reference to FIGS. 5 and 7. Notethat some steps shown in the flowchart do not necessarily have to occurin the order shown.

Method 500 begins with step 510. In step 510, a read of one or more RFaddressable sensors is initiated. In an embodiment of the presentinvention, sensor data processing logic 355 includes logic thatperiodically initiates sensor read communications. For example, sensordata processing logic 355 may automatically initiate a sensor read everysecond, every minute, or every 15 minutes. A sensor read may also beinitiated manually via the user interface 346 of wireless sensor reader140/340. For example, a user may initiate a read by activating a displayicon or option. In an embodiment, a user may initiate a read by pressinga series of keys on the device keypad (e.g., *2222) or by pressing aspecifically configured sensor read button. Alternatively, if the devicesupports voice activated commands, the user may initiate a sensor readby speaking the appropriate command.

In addition, a sensor read can be initiated remotely over datacommunications network 175 or the wireless network 170. FIG. 10 depictsa method 602 for remotely initiating a sensor read according toembodiments of the present invention. Method 602 begins with step 603.In step 603, the wireless sensor reader 140/340 receives a connectionsignal from an end user device 182. As would be appreciated by a personskilled in the relevant art(s), the type and format of the connectionsignal depends upon the implementation of the end user device 182 andthe wireless sensor reader 140/340. For example, if the wireless sensorreader 140/340 is also a wireless telephone device, the connectionsignal may be a telephone call by the end user device to the wirelesssensor reader. Alternatively, end user device may be a data terminal. Inthis example, the connection signal may be any type of datacommunications connection signals.

In step 605, the wireless reader 140/340 connects to the end user deviceover a communications network.

In step 607, the wireless reader 140/340 receives initiation signal(s)from the end user device. As would be appreciated by a person skilled inthe relevant art(s), the type and format of the initiation signal(s)depends upon the type and format of the connection signal. If atelephone connection is established, then the initiation signals may bea series of dual tone multifrequency (DTMF) signals or a voice command.Control then proceeds to step 520.

Returning to FIG. 9, in step 520, the wireless sensor reader 140/340communicates RF signals to one or more addressable sensors 520. These RFsignals can serve a dual purpose. They can initialize the RF addressablesensors for communications and provide operating power to the sensors.

Based on the details provided during read initiation, the wirelesssensor reader 140/340 may perform a sensor read of the entire populationof RF addressable sensors 102 or may perform a read of a specific set ofRF addressable sensors. In step 530, the reader determines whether toread the entire RF addressable sensor population 102 or one or morespecific RF addressable sensors 110. If the entire population is to beread, operation proceeds to step 550. If one or more specific sensors110 are to be read, operation proceeds to step 540.

For example, a user may obtain (e.g., purchase) a batch of RFaddressable sensors. The user may store the tag identification numbersassociated with each RF addressable sensor in the wireless sensor readerprior to initiating a read of the sensors. The reader can then isolateonly those specific RF addressable sensors stored in the wireless sensorreader.

In step 540, RFID tag processor 356 isolates (e.g., singulates) thespecific RF addressable sensor 110 to be read. Processor 356 may isolatea sensor 110 through an interrogation protocol, or other mechanism. Fordetails on methods for isolating a specific tag, see pending U.S.Application entitled, “Radio Frequency Identification Architecture,”referenced above. As would be appreciated by persons skilled in therelevant art(s), other protocols and methods for reading and isolatingtags can be used with the present invention.

In step 542, the wireless sensor reader 140/340 can, in addition tomerely recognizing the presence of an RF tag or RF addressable sensor,instruct the specific RF addressable sensor 110 to obtain sensor data.This can be done via a predefined command. In an alternate embodiment,RF addressable sensor 110 automatically signals sensor data to wirelesssensor reader 140/340 upon being isolated. In this embodiment, step 542is optional.

In step 544, the wireless sensor reader 140/340 receives the sensor datafrom the RF addressable sensor 110. Sensor data can include dataconfirming the proximity (i.e., the presence of) a sensor, sensorelement output data, sensor table data, reference data, and/or otherdata.

In step 546, the wireless sensor reader 140/340 determines whether anyadditional specific RF addressable sensors are to be read. If noadditional sensors are to be read, operation proceeds to step 560. Ifadditional sensors remain to be read, operation proceeds to step 540.

In step 550, the RFID tag processor 356 isolates an RF addressablesensor 110 from the population 102 using a conventional general readprotocol such as binary tree traversal.

In step 552, the wireless sensor reader 140/340 instructs the identifiedRF addressable sensor 110 to obtain sensor data. This can be done via apredefined command. In an alternate embodiment, RF addressable sensor110 automatically signals sensor data to wireless sensor reader 140/340.In this embodiment, step 552 is optional.

In step 554, the wireless sensor reader 140/340 receives the sensor datafrom the RF addressable sensor 110.

In step 556, the wireless sensor reader 140/340 determines whether anyadditional RF addressable sensors remain to be read. If no additionalsensors remain to be read, operation proceeds to step 560. If additionalsensors remain to be read, operation proceeds to step 550.

In step 560, the wireless sensor reader 140/340 determines whether anyadditional processing must be done on the received sensor data. Ifadditional processing must be performed, operation proceeds to step 562.If no additional processing must be performed, operation proceeds tostep 570.

In step 562, the wireless sensor reader 140/340 determines whether theadditional processing is to be performed locally or remotely. Ifprocessing can be performed locally, operation proceeds to step 568. Ifprocessing is to be performed remotely, operation proceeds to step 564.For example, some types of processing may be too resource intensive toperform efficiently on the wireless sensor reader 140/340 or may requiredata not available to the wireless sensor reader 140/340. In thissituation, remote sensor processing is selected for the sensor data.

In step 564, the wireless sensor reader 140/340 can optionallycommunicate the received sensor data to sensor network processor 190over communications network 180. In an embodiment, the wireless sensorreader may also communicate additional data to the sensor networkprocessor 190 such as data needed to perform geolocation. Upon receipt,sensor network processor 190 may perform additional processing on thedata and/or perform geolocation to determine the location of the RFaddressable sensor 110 that generated the sensor data.

In step 566, wireless sensor reader 140/340 receives the processedsensor data from sensor network processor 190.

In step 568, sensor data processing logic 355 processes the receivedsensor data. If sensor data is not received, or data received is not thesufficient for continued user authentication, the wireless sensor readercan be partially or completely disabled.

In step 570, the received sensor data or processed sensor data canoptionally be displayed. In an embodiment of the present invention, thedata can be displayed via a user interface 346 on wireless sensor device140/340. In an alternate embodiment, the data may also be communicatedto one or more end user devices over communications network for display.Step 570 is optional.

FIG. 11A is a flowchart of a method 700A for basic RF addressable sensorread communications from the perspective of single RF addressable sensor110 according to an embodiment of the present invention. Method 700Awill be described with continued reference to FIGS. 5 and 6. Note thatsome steps shown in the flowchart do not necessarily have to occur inthe order shown.

Method 700A begins with step 710. In step 710, RF addressable sensor 110receives RF signals from wireless sensor reader 340. In an embodiment,step 710 includes the step where the received RF signal is used to powersensor 110. Furthermore, step 710 may include the step where sensor 110identifies itself to reader 340.

In step 720, sensor 110 receives a command from reader 340 to send backa confirming signal, or to obtain sensor data. Step 720 can be optional.In an embodiment of the present invention, RF addressable sensor 110obtains sensor data automatically each time a communication session witha reader 340 is initiated.

In step 730, analog sensor data is obtained by one or more sensorelements 291, 292 and/or 294 and communicated to ADC 252.

In step 740, ADC converts the analog sensor data into digital sensordata.

In step 780, the RF addressable sensor 110 communicates the digitalsensor data to wireless sensor reader 140/340. The details of thiscommunication are dependent upon the protocol used for communicationbetween the wireless sensor reader 140/340 and the RF addressable sensor110. In an embodiment of the present invention, the protocol used is abinary tree traversal protocol. In this embodiment, the tagidentification number signaled by the RF addressable sensor 110 mayinclude both the tag identification number stored in memory 246 and thesensor data obtained by the sensor elements. Alternatively, reader140/340 may place the RFID tag logic 244 in a command state. In thecommand state, the RFID tag logic responds to commands received from thereader. When the RFID tag logic 244 receives an obtain sensor datacommand signal, the RFID tag logic will signal the sensor data to thereader 140/340. In an embodiment, the sensor data communicated to reader140/340 may include temperature data, sensor data, reference data and/ordata stored in sensor data table 258.

FIG. 11B is a flowchart illustrating a method 700B of RF addressablesensor read communications from the perspective of an RF addressablesensor having local processing capabilities, according to an embodimentof the present invention. Method 700B will be described with continuedreference to FIGS. 5 and 6. Note that some steps shown in the flowchartdo not necessarily have to occur in the order shown.

Steps 710 through 740 are generally the same as steps 710 through 740discussed above in reference to FIG. 11A.

In step 750, the converted digital sensor data is communicated to sensorprocessing logic 245.

In step 760, the sensor processing logic 245 processes the convertedsensor data.

Step 780 is generally the same as step 780 discussed above in referenceto FIG. 11A.

In each embodiment herein, upon non-receipt of a return signal, ornon-receipt of a predetermined return signal and/or data from an RF tag,RF addressable sensor, or other remote coupled device, the portableelectronic device or wireless sensor reader can be partially orcompletely disabled.

All of the US patents and patent applications disclosed herein areincorporated herein by reference.

1. A portable electronic device, said portable electronic device beingdependently operable on being remotely coupled to at least one RFID tag,said RFID tag being disposed on one of a piece of jewelry or a portionof clothing worn on a person, such that upon removal of said jewelry orclothing said RFID tag is rendered inoperable and said electronic deviceis partially or completely disabled.
 2. The device of claim 1, whereinsaid electronic device is selected from the group consisting of cellulartelephone, Smartphone, tablet computer, net book computer, laptopcomputer, GPS system, virtual wallet, virtual car key, and virtual housekey.
 3. The device of claim 1, wherein said electronic device is enabledfor full operation when in communication with said RFID tag, but is atleast partially disabled when not in communication with said RFID tag.4. The electronic device of claim 4, wherein said RFID tag measures atleast one parameter from a user's biometrics.
 5. The electronic deviceof claim 1, wherein said RFID tag is disposed on a paper or plasticbracelet.
 6. (canceled)
 7. (canceled)
 8. (canceled)
 9. (canceled) 10.(canceled)
 11. (canceled)
 12. The electronic device of claim 5, whereinsaid RFID tag is destroyed upon removal of said bracelet.
 13. A portableelectronic device, said portable electronic device being dependentlyoperable on being remotely coupled to at least one RFID addressablesensor, said RFID addressable sensor being disposed on a piece ofjewelry or a portion of clothing worn on a person.
 14. The device ofclaim 13, wherein said electronic device is selected from the groupconsisting of cellular telephone, Smartphone, tablet computer, net bookcomputer, laptop computer, GPS system, virtual wallet, virtual car key,and virtual house key.
 15. The device of claim 13, wherein saidelectronic device is enabled for full operation when in communicationwith said RFID addressable sensor, but at least partially disabled whennot in communication with said RFID addressable sensor.
 16. Theelectronic device of claim 13, wherein said RFID addressable sensor isdisposed on a bracelet.
 17. The electronic device of claim 16, whereinsaid RFID tag is destroyed upon removal of said bracelet.
 18. A portableelectronic device, said portable electronic device being dependentlyoperable on being remotely coupled to at least one RFID addressablesensor, said RFID addressable sensor being programmable by said portableelectronic device.
 19. The device of claim 18, wherein said electronicdevice is selected from the group consisting of cellular telephone,Smartphone, tablet computer, net book computer, laptop computer, GPSsystem, virtual wallet, virtual car key, and virtual house key.
 20. Thedevice of claim 18, wherein said electronic device is enabled for fulloperation when in communication with said RFID addressable sensor, butat least partially disabled when not in communication with said RFIDaddressable sensor.
 21. The electronic device of claim 18, wherein saidRFID addressable sensor is disposed in close proximity to a user's body.22. The electronic device of claim 18, wherein said RFID addressablesensor is disposed on a bracelet.
 23. The electronic device of claim 22,wherein said RFID tag is destroyed upon removal of said bracelet.